Jumpers and Test Points

Solder Jumpers (JPx)

Jumper	Default	Function	Description
JP2	Bridged	Disable Power LED	Disconnect this jumper to disable the onboard power LED. Useful for power saving or stealth applications.
JP3	Bridged	Disable PPS LED	Disconnect to turn off the LED that blinks with PPS signal.
JP5	GND via 4.7kΩ	Magnetometer I²C Address Select	3-way jumper. Default connects ADSEL to GND via 4.7kΩ → I²C address 0x12. Bridge the alternate pad to 3.3V via 1kΩ to change to 0x13 (per BMM350 datasheet).
JP6	Open	Bridge UART/I²C 5V ↔ USB-TTL 5V	Used to connect or isolate the 5V rail between GPS port and USB-TTL input. Bridge only if both share power safely.

Test Points (TPx)

Test Point	Signal	Description
TP1	Event Pin	GNSS event input (used for time-stamping or external edge-triggered events).
TP2	PPS Output	1Hz Pulse Per Second signal output from the GNSS module.
TP3	SafeBoot	Used to pull the GNSS module into firmware recovery (SafeBoot) mode.
TP4	VCC (after protection diode)	Measures input voltage after the reverse-polarity protection diode.